The present invention relates to an image forming apparatus including an image carrier in the form of, e.g., a photoconductive drum or a photoconductive belt and more particularly to a developing device included in an image forming apparatus for developing an electrostatic latent image formed on the surface of an image carrier by causing a thin layer of developing liquid to contact the latent image.
It is a common practice with a developing device of the type using a developing liquid, particularly a viscous developing liquid, to cause the liquid to form a thin layer on a developer carrier implemented as a roller or a belt. The developing liquid on the developer carrier is brought into contact with the surface of a drum, belt or similar photoconductive element, thereby developing a latent image formed on the above surface.
The problem with the developing device of the type described is that the film formed on the photoconductive element by the developing liquid after development is not uniform in thickness in the axial direction of the photoconductive element. This is ascribable to fine undulation, generally referred to as ribs, occurring in the axial direction of the photoconductive element and dependent on the viscosity and other properties of the liquid, the linear velocity and configurations of the image carrier and photoconductive element, etc. Should a toner image be transferred to a paper or similar recording medium under the above condition, there would occur the deformation of thin lines, contamination of background and other various troubles deteriorating image quality.